Training for a marathon? You may want to load up on bacon and cream.
The upper echelons of the medical community are steadily warming up to those oft-maligned fatty foods. Last month, the federal government prepared new guidelines that drop low-cholesterol recommendations, because "cholesterol is not considered a nutrient of concern for overconsumption."
The federal guidelines follow a torrent of criticism from the likes of experts at the Harvard School of Public Health and the University of California-Los Angeles, who blame saturated fat paranoia on shoddy correlational studies that ended up driving health conscious consumers into high-carb diets.
Now, as the majority of doctors move away from considering cholesterol a health threat, a cadre of medical researchers are arguing that high-fat diets may in fact be the perfect fuel for physically active people.
“From an evolutionary standpoint, a high-fat performance diet makes sense,” Ohio State University Professor Dr. Jeff Volek told the New York Times. Volek claims that (we're not kidding) a diet of nearly pure fat—85 percent of total calories per day—is the ideal endurance strategy for athletes and marathon hopefuls.
Volek argues that a high-fat diet provides both the brain and body with a slow burning source of fuel, unlike quick-acting carbs.
In a review of research published last month in the European Journal of Sports Science, Volek argues that a high-fat diet provides both the brain and body with a slow burning source of fuel, unlike quick-acting carbs.
And fat is more than just a steady energy source, it also catalyzes the production of ketones, a molecule that "could extend human physical and mental performance beyond current expectation." During acute fasting or carb-restriction, the brain can substitute ketone molecules for fuel.
Part of the novelty with Volek's review is that it looked at Ketone-adapted athletes over the long term. For instance, one study of off-road cyclists found that ketogenic diets hurt performance for the first three weeks, but helped over the long term as the athletes’ bodies adapted to use energy more efficiently.
"Since endurance athletes can metabolize fat more efficiently, low carbohydrate, high-fat diets should be preferred to carbohydrate loading as a nutritional strategy for increased performance," the research team concluded.
However, it's not all rainbows and sunshine for bacon-munching athletes. High-fat diets are still associated with lower performance for super-intense exercise; that means weight-lifting, CrossFit, football, or anything else performed at closer to 100 percent effort needs some carbs. Biking and running are intense, but its a steady-state intensity that rarely requires an all-out sprint.
Marathoners may wonder: What’s a diet of 85 percent fat like? I actually experimented with a super-fat diet earlier this year. For almost a month, I chugged cream in the morning and washed it down with bacon. It's more delicious than it sounds. Drinking high-quality cream tastes like slurping up a melted bowl of ice-cream, and bacon is, well, a gift from the gods. Combined with avocados and heavily olive-oil dressed salads, high-fat diets are actually quite pleasant.
Indeed, the dietary strategy for distance running might just end up being one of the best parts of marathon training: "Sign up for a marathon, eat lots of bacon." Sometimes, science is nutritious and delicious.